Chaos Ancient Gear Giant (Quarter Century Secret Rare)

4 "Ancient Gear" monstersMust be Fusion Summoned and cannot be Special Summoned by other ways. Unaffected by Spell/Trap effects. Your opponent's monsters cannot activate their effects during the Battle Phase. This card can attack all monsters your opponent controls, once each. If this card attacks a Defense Position monster, inflict piercing battle damage to your opponent.